1. Field of the Invention
the present invention generally relates to a methods and system for electrochemistry and biosensor applications, more specifically to functionalized nitride nanomaterials for electrochemistry and biosensor applications.
2. Description of the Related Art
Starting from the date in the discovery of the double helix structure of DNA, the technology of biology has grown from a purely descriptive and phenomenological discipline to that of a set of advanced molecular sciences. Amongst these advanced molecular sciences, bio-sensing is an important area used in such technical areas as clinical diagnosis, medicine, and bioengineering. Sensing single or minuet amount of biomolecules and/or chemicals requires integration of the highly selective recognition properties of biomaterials with unique electronic, photonic, and catalytic features of nanomaterials. Proteins, nucleic acid fragments and their biomolecular complexes have nanometric dimensions comparable with the inorganic nanomaterials, of which the inherently high surface-to-volume ratio offers the opportunity for efficient bio-binding and superb sensitivity in detecting biomoleules. A wide range of nanomaterials and sensing techniques, including absorbance (via surface plasmon), electrochemical or electrical, colorimetry, photoluminescence, and chemiluminescence, are known to have been explored. Though, for decades, several types of materials from metal, silicon to II-VI semiconductors and magnetic materials have attracted immense interest in biotechnology, III-V semiconductors have been left out, despite of same's unique optoelectronic properties and well-known non-toxicity and biocompatibility.
The element carbon is one of the typical widely investigated and heavily studied materials. The form the carbon studied includes graphite, diamond, C60, or carbon nanotube. In FIG. 1(a), a depiction of the cyclic voltammograms of Pt, glassy carbon and diamond showing typical potential windows of 0.5, 1.5, and 2.5 Volts are shown respectively. In contrast, FIG. 1(b) depicts the cyclic voltammograms of diamond electrodes with typical potential window less than 2.5 Volts.
A summary of electrochemistry results of the carbon materials is reported by Loh et al. as shown in FIG. 2, in which boron doped diamond exhibits the best performance with the largest potential window and the lowest background current. In summary, a potential window of less than 2.5 Volts is reported for all kinds of electrode materials. More specifically, in FIG. 2, a set of electrochemical potential windows of various electrodes in pH 7 PBS, CV data for boron-doped diamond (BDD), multiwalled carbon nanotube (MWCNT), carbon nanofiber (CNF), and fullerene is depicted.
Nitride materials, with wide and direct band gap, are known to be growing rapidly as a leading optoelectronic material. Recent progress in GaN and InN nanowires (NWs) has attracted huge attention for realizing nanosize ultraviolet or blue emitters, detectors, high-speed field-effect transistors, and high-temperature microelectronic devices. Meanwhile, one-dimensional (1D) nanostructures, with lateral dimensions in the nanometric range, have already been proposed as potential building blocks for the future nanoelectronic devices. Among them, novel nanobioelectronic sensors using the combination of biomolecules with functionalized 1D nanostructures show significant potential.